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Tetrandrine citrate eliminates imatinib-resistant chronic myeloid leukemia cells in vitro and in vivo by inhibiting Bcr-Abl/β-catenin axis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第11期13卷 867-874页

作者： Xiao-hua XU Yi-chao gan Gen-bo XU Ting CHEN Hong ZHOU Jin-fen TANG Ying GU Fei XU Ying-ying XIE Xiao-ying ZHAO Rong-zhen XU Department of Hematology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Department of Cancer Institute the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

Objective:To evaluate the effects of tetrandrine citrate, a novel tetrandrine salt with high water solubility, on the growth of imatinib (IM)-resistant chronic myeloid leukemia (CML) in vitro and in vivo, and reveal action molecular mechanisms. Methods:Cell viability in vitro was measured using methyl thiazolyl tetrazolium (MTT) assay. CML cell growth in vivo was assessed using a xenograft model in nude mice. Bcr-Abl and β-catenin protein levels were determined using Western blotting. Bcr-Abl messenger RNA (mRNA) was measured by reverse transcription polymerase chain reaction (RT-PCR). Flow cytometry (FCM) was used to determine cell cycle status. Results:Tetrandrine citrate inhibited the growth of IM-resistant K562 cells, primary leukemia cells, and primitive CD34 + leukemia cells, and their inhibition concentration that inhibited 50% of target cells (IC 50 ) ranged from 1.20 to 2.97 μg/ml. In contrast, tetrandrine citrate did not affect normal blood cells under the same conditions, and IC 50 values were about 10.12-13.11 μg/ml. Oral administration of tetrandrine citrate caused complete regression of IM-resistant K562 xeno-grafts in nude mice without overt toxicity. Western blot results revealed that treatment of IM-resistant K562 cells with tetrandrine citrate resulted in a significant decrease of both p210 Bcr-Abl and β-catenin proteins, but IM did not affect the Bcr-Abl protein levels. Proteasome inhibitor, MG132, did not prevent tetrandrine-mediated decrease of the p210 Bcr-Abl protein. RT-PCR results showed that tetrandrine treatment caused a decrease of Bcr-Abl mRNA. FCM analysis indicated that tetrandrine induced gap 1 (G 1 ) arrest in CML cells. Conclusions:Tetrandrine citrate is a novel orally active tetrandrine salt with potent anti-tumor activity against IM-resistant K562 cells and CML cells. Tetrandrine citrate-induced growth inhibition of leukemia cells may be involved in the depletion of p210 Bcr-Abl mRNA and β-catenin protein.

关键词： Chronic myeloid leukemia Imatinib-resistance Tetrandrine citrate Bcr-Abl protein β-catenin protein

Distributed Adaptive Attitude Synchronization of Multiple Spacecraft with External Disturbances

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Distributed Adaptive Attitude Synchronization of Multiple Sp...

第25届中国控制与决策会议

作者： Dapeng Yang Xiangdong Liu chao gan Yaohua Guo Key laboratory for Intelligent Control ＆ Decision of Complex Systems Beijing Institute of Technology

ISBN: (纸本)9781467355339

This paper considers the distributed attitude synchronization problem for multiple spacecraft with external disturbances. Distributed discontinuous adaptive controller is designed based on the relative attitudes and angular velocities of neighboring spacecraft and attitude synchronization can be reached for any communication graph containing a directed spanning tree. To tackle the chattering effect caused by the discontinuous controller, a continuous controller is further proposed, under which both the synchronization errors and the adaptive gains are ultimately bounded. Extensions to the case with a leader-follower communication graph with the leader as the spanning tree’s root are further studied.

关键词： Multiple Spacecraft Attitude Synchronization Distributed Control Cooperative Control

Identification of drilling stick-slip vibration conditions based on Empirical Mode Decomposition threshold denoising and Support Vector Machine

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Identification of drilling stick-slip vibration conditions b...

第三十九届中国控制会议

作者： Ke Zhang Weihua Cao chao gan Wenkai Hu School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems

The characteristics of the normal and stick-slip vibration signals reflect the drilling conditions, which is significant in recognizing them. In this paper, a new method that combines the Empirical Mode Decomposition（EMD） threshold denoising and Support Vector Machine（SVM） is proposed to classify these characteristics. First, the EMD threshold denoising method is introduced to denoise the raw signals of the drill string vibration. Second, the features of these characteristics are selected by the Intrinsic Mode Function（IMF） energy entropy and marginal spectral energy. Last, the drilling conditions are classified and identified by the Support Vector Machine（SVM）. The simulation results show that the identification accuracy of the proposed method is higher than the conventional methods.

关键词： Stick-slip Empirical Mode Decomposition Threshold denoising Intrinsic Mode Function energy entropy Marginal spectral energy Support Vector Machine

A pulse position coding-based mud pulse signal identification algorithm for Measurement While Drilling(MWD) system

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A pulse position coding-based mud pulse signal identificatio...

第32届中国过程控制会议(CPCC2021)

作者： Ziliang Yu Weihua Cao chao gan Min Wu School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education

Accurate identification of mud pulse signal is crucial for Measurement While Drilling(MWD) system due to its vital role in improving the drilling safety and *** this paper,a pulse position coding-based mud pulse signal identification algorithm is proposed for MWD system via two *** the signal preprocessing stage,wavelet filtering is introduced to reduce the noises in the raw mud pulse ***,a polynomial fitting-based detection method is used to remove the baseline drift in the *** the signal identification stage,a pulse signal position identification model is established to detect the pulse position,which does not need to set the detection threshold *** comparison results demonstrate that the proposed method has higher identification efficiency and accuracy than the conventional methods.

关键词： Mud pulse signal Wavelet analysis Polynomial fitting Pulse position identification model

Molecular mechanisms of apoptosis in hepatocellular carcinoma cells induced by ethanol extracts of Solanum lyratum Thumb through the mitochondrial pathway

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World Journal of Gastroenterology 2017年第6期23卷 1010-1017页

作者： Xiao-Qiang Mo Hong-Yu Wei gan-Rong Huang Ling-Yuan Xu Yu-Li Chen Jiang Qi Wei Xian Yan-Chun Qin Lian-Deng Wei Li-Juan Zhao Yan-Qiang Huang Wei Xing Hong-Qin Pu Peng-Ya Wei chao-gan Li Qiu-Chun Liang Breeding Base of Microbial Infection Key Laboratory in the West Guangxi Youjiang Medical University for Nationalities Affiliated Hospital of Youjiang Medical University for Nationalities

AIM To explore the induction effects and mechanism of Solanum lyratum Thumb(ST) on human hepatocellularcarcinoma SMMC-7721 cells through the mitochondrial *** The experiments were conducted on three groups: an experimental group (with ST ethanol extracts' concentration being 2.5, 5 and 10 mg/L), a negative control group (with only nutrient solution, 0 mg/L ST ethanol extracts), and a positive control group (2.5 mg/L DDP). The inhibition rate of cell proliferation was checked by using the methyl thiazolyl tetrazolium method, and cell apoptosis was tested by TUNEL method. Furthermore, RT-PCR was used to examine m RNA expression of Fas, Fas L, caspase-8, caspase-3, p53 and Bcl-2 *** Compared with the negative control group, the inhibition and apoptosis rates of the experimental group with different concentrations of ST extracts on human hepatocellular carcinoma SMMC-7721 cells significantly increased(P<0.05). Besides, the m RNA expression of Fas L and Bcl-2 significantly decreased(P<0.05) while the m RNA expression of Fas, caspase-8, caspase-3 and p53 increased significantly. When compared with the positive control group, the experimental groups with 5 mg/L ST ethanol extracts showed effects similar to the positive control *** ST ethanol extracts induced the apoptosis of hepatocellular carcinoma SMMC-7721 cells through up-regulated Fas, caspase-8, caspse-3 and p53, and down-regulated Fas L and Bcl-2 in the mitochondrial pathway.

关键词： Solanum lyratum Thumb hepatocellular carcinoma cell cell apoptosis mitochondrial pathway molecular mechanism

Preparation and physical properties of p-MgFe2O4-p-NiFe2O4 mixed ionic magnetic liquid

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Preparation and physical properties of p-MgFe2O4-p-NiFe2O4 m...

中国化学会第九届全国无机化学学术会议

作者： Qiuhua Xu Huang Yan chao gan Dongsheng Hu Yu Xie Department of Materials Chemistry Nanchang Hang Kong University

Using chemical coprecipitation preparation of p-Mg Fe2O4 and p-Ni Fe2O4 magnetic nanoparticles, Then the prepared magnetic particles with an acid and deionized water by mixing in proportion to get different volume fraction of unit ionic magnetic fluid. Finally, two kinds of unit magnetic liquid that the volume fraction is same in a volume ratio of 1:1 by mixing is to be binary ionic magnetic liquid p-Mg Fe2O-p-Ni Fe2O4. Characterized analyzing of the magnetic nanoparticles by XRD, compared with the standard ratio of cards, finding the location of the peak to move a small range to the direction of small angle, also finding some miscellaneous peak, it may be due to a little residual impurities in the experiment. Still can see the nanoparticles of p-Mg Fe2O4 and p-Ni Fe2O4 are amorphous state, the shapes of the two kinds of particles are approximately spherical. Measuring the intensity of the transmission light of unit ionic magnetic fluid and binary ionic magnetic fluid under an applied magnetic field. The results show that both the p-Mg Fe2O4 and p-Ni Fe2O4 magnetic liquid, the intensity of transmission light does not substantially change with the applied magnetic field strength varies, But the intensity of transmission light will decrease with the increase of magnetic liquid volume fraction. For binary ionic magnetic liquids,circumstances are basically the same as unit of ionic magnetic *** observed changes in the microstructure of the magnetic fluid over time in different intensity of uniform magnetic field with an optical microscope, it is found that the magnetic particles of the three kinds of magnetic fluids move very slow in the magnetic field. This also confirms the phenomenon that the intensity of transmission light varies with the change of the intensity of the magnetic field.

关键词： magnetic fluid binary magnetic fluid chemical coprecipitation XRD magneto-optical effect

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基于动态波长分配的WDM-PON技术研究

光通信技术 2008年第11期32卷 8-11页

作者：石磊甘朝钦上海大学通信与信息工程学院特种光纤与光接入网省部共建重点实验室上海200072

WDM-PON是未来宽带光接入网的发展趋势,基于动态波长分配的WDM-PON在系统安全和网络带宽升级等方面具有独特优势。文章介绍了WDM-PON的基本结构及运行原理,着重对基于动态波长分配的WDM-PON作了研究,并对其中涉及到的一些关键技术(如多... 详细信息

WDM-PON是未来宽带光接入网的发展趋势,基于动态波长分配的WDM-PON在系统安全和网络带宽升级等方面具有独特优势。文章介绍了WDM-PON的基本结构及运行原理,着重对基于动态波长分配的WDM-PON作了研究,并对其中涉及到的一些关键技术(如多波长光源、ONU光源和MAC协议等)作了深入分析和探讨,总结了WDM-PON的发展现状,提出了应用前景。

关键词： WDM-PON 动态波长分配多波长光源 MAC协议

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CTR的导电机理研究

传感技术学报 2006年第2期19卷 454-456页

作者：孙健甘朝钦刘英吴宗汉南京师范大学电气与自动化工程学院南京210042 东南大学物理系南京210096 江苏兴顺电子元件厂江苏兴化225700

为了优化CTR(CriticalTemperatureResister)产品性能,从微观上分析CTR晶粒体相变临界特征和粒界的电势垒,得出CTR临界阻温特性是由晶粒体导电性能和粒界电势垒共同决定,即“晶粒体-粒界”模型。运用此模型对不同配料比样品的临界阻温特... 详细信息

为了优化CTR(CriticalTemperatureResister)产品性能,从微观上分析CTR晶粒体相变临界特征和粒界的电势垒,得出CTR临界阻温特性是由晶粒体导电性能和粒界电势垒共同决定,即“晶粒体-粒界”模型。运用此模型对不同配料比样品的临界阻温特性进行分析,得出V_2O_5P_2O_5Fe_2O_3配料比是影响CTR性能的关键因素。

关键词：临界特性阻温特性晶粒体粒界

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垄断与竞争:中国医疗行业市场效率分析

经济与管理研究 2020年第6期41卷 47-58页

作者：于良春甘超山东大学经济学院济南250100

公立医院在医疗市场的垄断势力导致行业效率低下,医疗费用快速上涨。民营资本进入在一定程度上改善了医疗市场结构,提高了行业竞争程度。本文分析竞争与医疗行业效率的内在逻辑,并选取2010—2017年省际面板数据,实证分析竞争是否提高了... 详细信息

公立医院在医疗市场的垄断势力导致行业效率低下,医疗费用快速上涨。民营资本进入在一定程度上改善了医疗市场结构,提高了行业竞争程度。本文分析竞争与医疗行业效率的内在逻辑,并选取2010—2017年省际面板数据,实证分析竞争是否提高了医疗行业效率。研究发现:民营医院数量的增多能够引起医疗行业效率提高,但在医疗服务提供方面,目前公立医院的垄断地位仍难以打破,民营医院进入对医疗行业效率的影响尚不显著;需要在消除制度性进入障碍,形成有效竞争的市场结构,促进医疗行业要素流动等方面进一步深化医疗体制的改革。

关键词：医疗行业市场结构医院竞争医疗效率民营医院